Butterfinger Cake 1 german chocolate cake mix 1 can eagle brand milk 6-8 butterfinger candy bars 1 (8-oz) tub cool whip Bake cake as directed on the cake mix package. When cake is done and while still hot, poke holes in it. Pour 1 can of eagle brand milk over top. Crush 3 to 4 butterfinger candy bars, sprinkle on top. Take 1 (8-oz) tub of cool whip and 3 to 4 butterfinger candy bars (crushed) and mix together. Spread on cooled cake.